1. Field of the Inention
The present invention relates to sealed rare earth magnets and methods for manufacturing the same, and more specifically relates to sealed rare earth magnets used in motors or semiconductor manufacturing devices, and methods for manufacturing the same.
2. Description of Related Art
Rare earth magnets have utilized in various fields such as motors and semiconductor manufacturing devices. For example, when rare earth magnets are utilized in motors for fuel cell vehicles, there is a risk that the rare earth magnets will be exposed to a hydrogen gas atmosphere. In addition, etchers and the like in semiconductor manufacturing devices sometimes utilize hydrogen gas as the reacting gas. In such a case, there is a possibility that when rare earth magnets are used in semiconductor manufacturing devices, there is a risk that they will be similarly exposed to the hydrogen gas atmosphere. Rare earth magnets suffer from hydrogen embrittlement. Therefore, even if various anti-oxidation surface treatment methods such as nickel plating, copper plating, aluminum ion plating and resin coating are utilized on the magnet surface, when in a hydrogen atmosphere, there is the problem of the risk that the magnet will be destroyed due to hydrogen embrittlement. As a rare earth magnet in which countermeasures are taken against hydrogen embrittlement, Japanese Patent Application Unexamined Publication No. H11-087119/1999 A, which is herein incorporated by reference, discloses a rare earth magnet that has a hydrogen storage alloy, which shows a plateau pressure of 0.001 to 0.1 MPa at a temperature of 400 K and above, as a surface treatment film, wherein the rare earth magnet is preferably Nd2Fe14B1, and wherein the surface treatment film is preferably made by providing a Pd plating on the surface of the Nd2Fe14B1.